اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدObservation of a structure in $e^+e^- to phi eta^{prime}$ at $sqrt{s}$ from 2.05 to 3.08 GeV
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The process $e^{+}e^{-} to phi eta^{prime}$ has been studied for the first time in detail using data sample collected with the BESIII detector at the BEPCII collider at center of mass energies from 2.05 to 3.08 GeV. A resonance with quantum numbers $J^{PC}=1^{--}$ is observed with mass $M$ = (2177.5 $pm$ 4.8 (stat) $pm$ 19.5 (syst)) MeV/${ it{c}^{mathrm{2}}}$ and width $Gamma$ = (149.0 $pm$ 15.6 (stat) $pm$ 8.9 (syst)) MeV with a statistical significance larger than 10$sigma$. The observed structure could be identified with the $phi(2170)$, then the ratio of partial width between the $phi eta^{prime}$ by BESIII and $phi eta$ by BABAR is ($mathcal{B}^{R}_{phi eta}Gamma^{R}_{ee})/{(mathcal{B}^{R}_{phi eta^{prime}}Gamma^{R}_{ee})}$ = 0.23 $pm$ 0.10 (stat) $pm$ 0.18 (syst), which is smaller than the prediction of the $sbar{s}g$ hybrid models by several orders of magnitude.
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